- (North American English mail slot)
a narrow opening in a door or wall through which mail is delivered （门或墙上的）信箱 
- (North American English mailbox)
a small box near the main door of a building or by the road, which mail is delivered to （建筑物大门口或路旁的）信箱 - (also postbox (British English), North American English mailbox)
a public box, for example in the street, that you put letters into when you send them 邮筒；邮箱 
